The extra power comes courtesy of redesigned cylinder heads and new camshafts, along with modifications to the electronic engine-management system. The kit also has a new variable resonance intake system, an additional center radiator to keep the hotter engine cool, sports exhaust and the Sport Chrono package with dynamic engine mounts. A titanium-color engine cover completes the package.

Porsche claims that the Powerkit drops the 911's 0-to-60-mph time from 4.3 seconds to 3.9 seconds, while top track speed increases from 188 mph to 191 mph. Porsche says the kit has no effect on fuel economy, which remains at 20 mpg in the city, 27 mpg on the highway, despite the 7 percent power increase. Porsche says it will announce pricing for the Powerkit prior to its debut in September.

Porsche Exclusive also offers new aerodynamic pieces for the 911, including a new front apron that extends lower to the ground and the air intakes from the Sport Design package—for $4,990. The Carrera-style ducktail wing is offered, along with the Aerokit Cup ($5,990), which adds a fixed wing over the standard rear spoiler. The Aerokit also comes with a new front spoiler lip and additional air intakes.

The aero bits are available for order now via Porsche's online configurator; the Powerkit will be available in early fall.